Refrigerating device



Dec. 24, 1929. D. F. KEITH REFRIGERATING DEVICE ts-Sheet Filed June 27.1927 W725i. M m

ATTORNEY.

Dec.' 24, 1929. KE|TH 1,740,737

REFRIGERATING DEVI CE Filed June 27. 1927 3 Shets-Sheet 2 A TTORNEY.

Dec. 24, 1929.

D. F. KEITH REFHIGERATING DEVICE Filed June 27. 1927 3 Sheets-Sheet 3 ATTORNE Y.

-- Patented Dec. 24, 1929 PATENT OFFICE DAVID FORBES KEITH, F TORONTO,ONTARIO, CANADA REFRIGERATING DEVICE Application" filed June 27,

My invention relates to refrigerating devices operating upon theabsorption systeni,

'- and more particularly to units which are separable from therefrigerator boxes or other coolers in which they are intended to beemployed. I While my device is a departure in some of its principles ofoperation from standard absorption systems, in that there are no checkvalves employed by me, it operates through a similar cycle to allintermittent absorption systems, that is to say, I provide tworeceptacles, one -a generator-absorber, which containsa suitable liquid,such as water, and the other an evaporator-condenser, which contains asuitable refrigerant, such as ammonia, with suitable connecting pathsbetween the two receptacles so that when the generatorabsorber isheated, the gases will pass over into the evaporator-condenserreceptacle, by

e one path, and when the generator-absorber is permitted to become cool,it will reabsorb the gases, as they volatilize in theevaporatorcondenser receptacle, said gases pass back and are absorbed intheliquid in the generatorabsorber. with the result of absorption ofheat v (production of cold), within and about the' evaporator-condenserreceptacle.

As intimated above, one of my obiects is to i provide a refrigeratingunit of light weight. Another object is to provide means in connectionwith a novel arrangement which guides the user in locating the unitduring the generation period, the refrigerating period, and in drainingback the water of condensation into the generator-absorber, for theretention of sufiicient liquid to serve the function of a seal when thedevice is in operation.

Other objects are to provide a system of absorption which operatesefliciently without the use of mechanical valves,'to provide a method ofdehydrating and cooling the gas passing from the generator, and toprovide an efiicient method of incr easing the rate of heat exchangebetween thegenerator-absorber and its surroundings. It is also my objectto'provide a simple and effective method of attaching metal fins to thegenerator shell.

A general object of my invention is to pro-. 60 vide a structurewhichwill be simple to make,

1927. Serial No. 201,904.

and fool-proof in operation, and which can be readily moved about duringthe respective periods of generation and absorption, so that thegenerator-absorber can be placed over a flame, during generation, andthe evaporatorcondenser receptacle be placed into a water vessel duringcondensation and a suitable box, vessel or receptacle during evaporationand absorption, with the generator-absorber on the outside of the saidbox, in the last instance. 0

In this connection, it is my object to make the two main receptacles ofspherical shape and light in weight and to connect them by means oftubular means which will serve as a support for the device when in use,and to which a handle for moving it about may be applied.

It is my object to provide for an automatic warning which will indicateby sound or change in color, when the operation of generation has beencompleted.

It is my object toprovide in connection with the evaporator-condenserelement for a simple mode of freezing desired materials in a tray.

It is my object to provide in connection with my device for a simplemeans of assuring a proper cooling action in the evaporatorcondenserelement during condensation. preferably by means of a suitablecirculation deso vice in the nature of a dome which sets up coolingcurrents of water about the evaporator-condenser shell, and acirculation throughout the entire water vessel.

The above and various other advantages, as I provide by thatcertainconstructionand arrangement of parts, of which a typical examplewill be hereinaft'er more specifically pointed out and described. andthe novelty of which will be set forth in the appended claims.

In the drawings I Figure 1 is a central longitudinal section takenthrough the selected example to be described, showing my invention.

- Figure 2 is a perspective thereof.

Figure 3 is a section on the line 33 of Figure 2,'showing-only thegenerator-absorber shell.

Figure 4 is a detail perspective of one of the cooling fins on the saidshell.

Figure 5 is a section illustrating the device 1, having an outlet tube 2which lets into the tube 3. The tube 3 is connected to a tube portion 4which is bent around at each end, and is connected to thegenerator-absorber. The

tube portion 4 is generally of U shape, as-

noted, but has a considerable portion of its length in what might betermed the base of the U shape. This tube portion 4 is to be used as ahanger for the device. It is also equipped with a handle 5 by. means ofwhich the device is manipulated, which handle is placed so that the twoparts of the structure are substantially balanced at the point where thehandle will be grasped. The shell has a chamber 1 formed therein, sameopening to the outside. Into this chamber an ice tray may be inserted.

The lower portion of the, tube 3 is closed by a base plate 3 and may besurroundedby an insulating shell in tubular form, as indicated at 3*.This ortion of the tube serves as a sump for condensed absorbent oroverflow.

The generator-absorber is formed of a spherical shell portion 7, havingheat exchange fins arranged about its surface, in vertical planes. Thesefins are a novel conception, and are formed of pieces of sheet metal 8,bent to form flanged channels, of which the flanges are soldered orotherwise attached to the shell.

The function of the fins is to exchange heat with their environmentby'both radiation and convection, more particularly the latter, be.-cause they form passages or flues for movement of air or other coollngfluid, up along the shell, within the channels. The passage of the airgreatly increases the cooling effect, and the section strengthens the.fins and reduces the cost. I find that the channel-like fins are a'verydecided advantage over the usual type of fin.

Mounted overthe top of the generator-absorber shell is a device having adome shaped body 9, which is soldered or otherwise attached to the shell7. The device has a base plate 10, which is formed up centrally at 11about the tubular end 7 of the shell 7 somewhat similarly to a cake pan.The central portion 11 is secured at its upper end to the dome bycrimping to form a substantially steam tight joint. The part 10 isspaced slightly from the dome, and a tube 12 is soldered to the top ofthe portion 9,land extends through the plate 10, communicating directwith the shell 7. A tube 12 extends from the tube 12 to the interior ofthe dome.

\Vater is placed into the interior of the dome through a small hole 13,and a whistle 14is set into the dome to be operated from steam escapingthrough the whistle tube extending through the closed end of the tube12. The water in the dome aids materially in dehydration or pre-coolingof the gas from the generator.

The result of the structure is that the water in the dome, when thegenerator-absorber is being heated, will rise in temperature, coinmenceto boil, and at a predetermined stage in the generation period, the rateof formation of steam, balanced against the rate of passage of steamthrough the gauged opening 13, will cause a'steam pressure sufficient tolift the water to a point where some of it will flow up through the tube12, so that it falls through the tube 12 against the shell 7. Thiswater, on reaching the hot generator shell 7 is flashed into steam whichcauses the whistle 14 to blow, and stops the water com ing up from thedome 9. W'hen the first portion of water has all been evaporated, thewhistle ceases to blow until the pressure has once more beensufiiciently built up to send down another portion of water. Inthis waya repeated action of thewhistle is secured.

The operator will be able to apply heat to the generator-absorber, andneed do nothing more until the whistle begins to blow, after which hewill'wait such time as is required,

The tubular upper end 7 of the shell 7 is closed at the entrance to theshell 7 by a partition or plate 15. The plate 15 has a hole for passageof the absorption pipe 16, which'extends down to a point below the levelof absorbent in the shell 7. It is quite important to have the lower endof the pipe 16 open and to terminate near the surface of liquid in theshell 7 when the absorption begins .to take place. This level isindicatedby the line B in Fig. 1. For circulation, the tube 16 may beset into the shell so as to surround the end.

of the tube 16, but not impede the efflux of gas from the mouth of thetube 16.

The closed lower end of the portion 7 forms in this portion of thesystem a liquid seal, and the tube 16 defines the level of absorbent, beit water or whatever agent is used,

so that normally the inflow into the shell 7 is through the tube 16, butthe outflow passes through another set of passages, and bubbles upthrough the liquid seal.

To provide this structure Ifind a simple mechanism to be as follows :Atube 17 extends from an opening through the plate 15,

JVlllCll permits generated gases to pass out of 3, and closed at thebottom. The vessel is secured in the tube 3 by means of spaced lips 20so that there is. a passage for generated gases around the outside ofthe vessel. The

. outlet tube 2 from the shell 1 is closed at the end, and has a seriesof holes 2 in it-s lower face. These holes provide the passage to andfrom the shell 1.

' The sump lies below the end of the tube 2, and the vessel isnormallyfilled with the a mixture of absorbent and refrigerant, usually water,and ammonia as stated. The hot gases passing down around vessel 20 arecooled by vaporizing the refrigerant from the mixture in the vessel 20and also by the contact with the tube 3 which is submerged in water.

The shell 1 has adcnie erected thereon in the shape of a spaced halfspherical dome 21, having a neck and mouth 21*, and held in place bymeans of spaced strips 21 2-.

I have not describedior shown in detail drain'openings, and pressurerelief valves, except that I have indicated at 23 a suitable pressurerelief device, and at 22 a suitable charging opening and plug.

When the deviceis employed in a refrigerator box or cabinet, which isthe typical use of the device, I provide a suitable box 26, having a lid26 hinged thereto, or otherwise removably set thereon, and leavingsufficient space at least for the insertion of the shell 1. Theside wallof the box has a groove 27 therein which will fit the tube 4, and chan-.neled to seat the bracket 32, or the lid and groove can be formed 'toco-operate in enclosing the box about the tube 4. The shell 1 is placedin the .box, and the lid closed down leaving the shell 7 outside. Insideof the box a strap or loop 28 is secured on the lower inside of the boxin such a position that the lower end of the tube 30am be thrusttherein, thus resisting the rocking tendency of the weight of the shell7 and holding the device against tipping.

As a water cooling means used in the cycle of operations as will bedescribed, I normally provide a water vesselor tub 30. This tub has abracket 31 on the outside. I locate on the under side of the tube 4, soas to be near the point where the tube bends down to the tube 3, abracket 32, in the form of a plate soldered in place, and presenting twoshoul- -ders 32 and 32".

Then the generator shell is being heated, the shell 1 is set into thetub of water, leaving the bracket 32 inside of the tub at its rim. Theshell 7, which is full of absorbent and refrigerant at the beginning ofthis operation, rests against the bracket 31, and the nature of thesupport is such that the weight of the shell 7 and its content acts toovercome the buoyancy of and to submerge shell 1.

For defining a draining position for the device, in the cycle ofoperations which will be described, I locate at the end-of the handle 5a foot 25, which can be rested on the floor or a table or othersupporting surface, and the location of the device in an invertedposition supported by the foot and the shell 7, as shown in Figure 6 isthus defined.

As described, the device will be considered as filled with absorbent,,usually water, to gether with dissolved refrigerant, for exampleammonia, so that the shell 7 is filled to a level such as that noted at34, the lower portion of 7 is filled to the level'noted at 35,

and the vessel 20 to the level noted at 36; The water dome, wherethis-form of signal is employed, will be considered as having watertherein. 3 At'the start of the operation the level 34 is correct, butwhen the refrigerant is fully generated, the level is at B.

The shell 1 is set into a tub of water as preferably indicated in Figure7, in which case the mouth of the dome neck is located below the levelof water in the tub. The shell 7 is placed over a heater 3B.

The application of heat causes the refrigerant gases to pass up throughthe tube 17 into the small container 18, which is closed except for thetube 19. Thecontainer or ves nection between the tubes 17 and 19. The

part 18 also assists in maintaining the level of liquid in the seal.

The effect of the water in the dome around the portion 7 of thestructure tends to imparta preliminary cooling. The refrigerant underpressure passing through the tube 17 and compartment 18, and downthrough the tube '19 bubbles up through the liquid absorbent in theportion 7 and thence passes into the tube portion 4. A small proportionof the absorbent is usually gasified along with the refrigerant.

Condensation of the absorbent in the compartment 18 and the tube 19results in a supply of liquid being kept up in the seal at 7 The gaspasses from the tube 4 into the tube 3, where it must follow the passagearound the outside of the vessel 20. Here t ie refrigerant gives up heatin two ways: (1) to the water in the tub, in which a portion of the tube3 is plunged at the time, and (2) to the vaporizing ofsuch refrigerantas is contained in the mixture in the vessel 20. This act of vaporizingthe refrigerant absorbs concontact.

siderable heat, and also returns the refrigerant to the system.

This cooling causes the absorbent to condense in the form of a mistcontained in the still 'gasified refrigerant, which mist will bedeposited upon surfaces withvwhich it must Somecolleets on the inside ofthe tube 3 and the outside of the vessel 20. The gases must passdown'around the tube 2 and up through the holes 2. In doing so,practically all of the mist is deposited and runs down into the sump inthe lower endof the tube 3.

The refrigerant fairly clear of absorbent medium by this time passesinto the cold ball 1, where it is condensed to a liquid, as a resultofits heat being given up to the walls of the cold ball, and thence tothe water in the tub.

- The condensation of the refrigerant starts to take place when thepressure resulting from the heating of the shell 7 builds up asufficient heat-within the shell 1 or cold shell.

The heating of the shell 7 is continued until the maximum desired amountof refrigerant in the system has been boiled out of the absorbent. Atthis period the warning whistle will begin to operate, and after it hasoperated for several periodic intervals, the hot shell is taken awayfrom the heater, and the heat turned 01f. It should be noted that'theliquid in the shell 1 Figure 1 at 1" is not present when the shell 7 isfilled to the level shown. The shell 1 is normally empty when the shell7 is full.

' tub. The bracket 31 holds the hot shell away from the tub and preventsthe device from tipping, so that the whole system weighs down thecoldshell, and keeps-it in the position indicated in Figure 7. The waterflows up around the dome and out through the.

mouth thereof, causing a circulation through the whole tub." If thesafety device in the cold shell should rupture, the refrigerant will beabsorbed or dissolved in the water of the'tub.

In placing the hot shell inthe tub, the shoulder 32 of the tube bracketis hooked over the edge of the tub, andthe shell 1 abuts the bracket, orrather the lower end of the tube 3 abuts it, resulting in keeping thehot shell down, and incidentally in resupplying water in the-steam domeon the hot shell,

. through the hole 13'therein.

The device is then placed into the refrigerator box, as explained, andthe hot ball being partially cooled, and this cooling being muchenhanced by the fins, as described, will continue to become lower intemperature. This lowers the pressure in the system, causes therefrigerant to-slowly evaporate in the cold ball, and to pass back fromthe cold shell in the same way that it entered it. The gases pass downthrough the tube 16, since they cannot pass through the liquid seal, andset up an agitation as they bubble into the absorbentin the hot shell.This action results in the great reduction of temperature of the shell 1and the tube 3. The absorbent is strongly a'vid for the refrigerant, andabsorbs it as fast as it enters through the tube 16, this action beinggreatly enhanced by the bubbling and agitation of the absorbent by theinflux of the gas. The bubbling and agitation results from the end ofthe tube 16 being near the surface of the liquid in the shell 7 and alsofrom the end of the tube being open.

When the refrigerant medium has sufficicntly passed back to the hotshell again, itis necessary before reheating to drain the system. Thisis so because what residue of the absorbent is left in the cold shelland the sump should be returned.

The device is set into the position as guided by the shoe on the handle,as described, and as shown in Figure 6, which establishes a level ofliquid in the system, about as shown in the dotted line A of Figure 1.The drainage having taken place, the device is righted again, whichresults in all of the liquid in the system flowing into the shell 7except suflicient t-o fill the vessel 20, and the liquid seal in theportion 7 Any excess will pass into the sump, but it will be difficultto even completely fill the Vessel 20, upon righting the device, due tothe proportions and shapes of the elements thereof.

Since there are no losses in the system, it will continue to function'inthe cycle noted, with-"intervals of absorption, drainage and generation.

I have not illustrated the seams formed making up the two shells, anduniting the tubular portions and shell together, as this may beaccomplished in any desired way.

Its inexpensiveness and easy operation, makes my device available fordomestic refrigeration at a cost which isvery much lower than presentsystems, and brings artificial refrigeration within the economicalresources of those of moderate means.

It will be evident that modifications of the structural details of mydevice may readily be made without departing from the invention therein,and I do not wish to represent that the embodiment of my inventionselected for purposes of illustration, is the only way in which myinvention can be brought to practical use.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is v 1. In combination, a refrigerator box,and a removable refrigerating unit therefor, said box having an opening-therein,a groove in the upper edge of the wall about said opening, saidunit having'its portions connected 'to provide separate paths for flowof gases in opposing directions, said passageways includmg a liquid sealcomposed mainly of the liquld absorbent used, means for defining aredraining position for said unit, and means for retaining liquid forreturn to the seal -upon righting the unit from redraining posi- 3. In arefrigerating device, a generatorabsorber, connections therefrom throughtwo passages, arliquid seal composed mainly of the liquid absorbent usedabove which one of the passages terminates, and within the liquid ofwhich the other passage terminates, a single passage from above the sealto an evaporator, a sump 1n said passage, and an evaporator to whichsaid single passage is connected above said sump.

. 4. In a refrigerating device, a generatorabsorber, connectionstherefrom through two passages, a liquid seal composed mainly of theliquid absorbent used above which one of the passages terminates, andwithin the liquid of which the other passage terminates, a singlepassage from above the seal to an evaporator, a sump in said passage,and an evaporator to which said connected above said sump, said partsbeing arranged so that all liquid will drain from the evaporator uponproper positioning of the device. I

5. In a refrigerating device, a generatorabsorber, connections therefromthrough two passages, a liquid seal composed mainly of the liquidabsorbent used'above which one of the passages terminates, andwithin'the' liquid of which the other passage terminates, asinglepassage fromabove the seal to an evaporator, a sump in saidpassage, and an evaporator to which said-single passage is connectedsingle passage is liquid seal when the device for refrigerant duringboiling of'i'and reabsorption, and a liquid seal-composed mainly of theliquid absorbent used for one of said passages at least, and meanswhereby the freezing element can be drained into the gen; eratorabsorber through said passages without destroying the liquid.v seal.

7. In a refrigerating device, a generatorabsorber, and a freezingelement connected thereto, including passageway forming means forrefrigerant during boiling off and re-' absorption, and aliquid sealcomposed mainly of the liquid. absorbent used for one of said passagesat least, and means whereby the freezing element can be drained into thegenerator-absorber through said passages without destroying theliquidseal, said structure having an overflow sump connected thereto.

8.-In'arefrigeration unit, a generator-absorber casing, acondenser-evaporator casing, tubular means connecting the same, andextending beyond the condenser-evaporator to form a sump, and a liquidcontainer located within said tubular means and defining influx andeiflux passages from the generator-absorber between it and the tubularmeans.

9. In a refrigeration unit, a generator-absorber casing, acondenser-evaporator casing, tubular means connecting the same, and extending beyond the condenser-evaporator to form a sump, and meanslocated within said tubular means and defining influx and eifluxpassages from the generator-absorber, includinga liquid container. u

10. In a refrigeration unit, a generatorabsorber casing, acondenser-evaporator casing, tubular means connecting the same, and

, to form a sump, and means located within said tubular means anddefining'influx and eifluxpassages from the generator-absorber,including a liquid container, said tubular means having a portion of itsbody arranged to serve as a support forboth casings upon an interveningWall.

11. In a refrigerating unita generatorabsorber and means-mounted uponsaid absorber and operated by heat, said means hav ing a soundingelement arranged to give warning upon predetermined temperatures of thegenerator-absorber, and comprising a retainer for water having a steambleed hole, and a discharge chamber of which the generator-absorberforms a wall, a sounding device in. the Wall of the discharge chamber,and a pressure operated overflow from the retained to the dischargechamber.

7 12. In agenerator-absorber, a casing therefor, a dome mounted uponthetop of-said casing, and having a water receptacle therein, spacedfrom the casing, and a portion of .which the casing forms a wall, havinga sounding device therein, and steam pressure operated means fordischarging water from the receptacle to the portion having the soundingdevice.

13. In a generator-absorber, acasingthere for, and heat radiation finsupon the casing extending other than horizontally and forriied ofinverted channels open at the top and bottom, for the pur ose described.

14:. In a generator-a sorber, a spherical shell therefor, and heatradiation fins thereon comprising inverted channel members open at thetop and bottom secured to the casing, and extending other than parallelwith the horizontal axis of the spherical shell.

15. In combination with a refrigerator cabinet, a refrigerating unithaving a generator-absorber-element, anda condenser-evap orator element,means connecting them together, said cabinet having an opening ofsufficient size to receive the condenser-evaporator, and a closure forsaid opening, and means within the cabinet for engaging thecondenser-evaporator, when supported'on the cabinet by the saidconnecting means.

16. In combination with a refrigerator cabinet, a refrigerating unithaving a generator-absorber element, and a condenser-evaporator element,means connecting them together, said cabinet having an opening ofsufficient size to receive the condenser-evaporator, and a closure forsaid opening, and means within the cabinet for engaging thecondenser-evaporator, when supported on the cabinet by the saidconnecting means, said cabinet having a groove therein in the wallthereof about said closure for retaining the said connecting means.

17. In combination with a refrigerator cabinet, a refrigerating unithaving a genera- '-tor-absorber element, a condenser evaporator element,and means connecting them to ether, said condenser-evaporator elementinc uding a tubular sump, said cabinet having an opening ofsuflicient'size to receive the condenser evaporator element, a closurefor said opening, and a retainer located within the cabinet for engagingsaid tubular sump, when the device is supported on the cabinet by saidconnecting means. V

18. In combination in a refrigeration unit,

a generator-absorber of spherical shape, a condenser-evaporator llkewiseof spherlcal shape, a tubular passage extending between said absorberand evaporator devices, said tubular passage containing all connectingmeans between said-devices, including a vessel for entrapping liquidtherein to form a cooling element between said two devices for a theflow of the refrigerant during the generation step of its cycle ofoperations.

19. In combination in a refrigeration unit,

a generator-absorber of spherical shape, a.

condenser-evaporator likewise of spherical shape, a tubular passageextending between said absorber and evaporator devices, said tubulerpassage containing all connecting purpose described.

20. In combination in a refrigeration unit, a generator-absorbercomprising a container portion for absorbent, an inlet therein in theform of a tube extending to a point below the level of absorbenttherein, tubular means extending from above the level of absorbent insaid container, a liquid seal applied about the exit end of said tubularmeans, and means for preventing a surge of the liquid of said sealthrough the said tubular means.

21. In combination in a refrigeration unit, a generator-absorbercomprising a container, a vessel forcontaining liquid located adjacentthereto, a tube defining the level of liquid in said vessel andextending to a point below the level of liquid in the container, andtubular means extending from above the liquid level in said container toa point below the liquid in said vessel, whereby a seal is pro- Vided.

22. In combination in a refrigeration unit, a generator-absorbercomprising a container, a vessel for containing liquid located adjacentthereto, a tube defining the level of liquid in said vessel andextending to a point below the level of liquid in the container, andtubular means extending from above the liquid level in said container toapoint below the liquid in said vessel, whereby a seal is proaevaporator element comprising a tubular passageway forming means, aliquid container located insaid passageway and requiring flow of gasesaround it, a'condenser shell connected to said tubular passageway meansbeyond the liquid container, and a sump located below the point ofconnection of the condenser shell.

24. In a refrigeration unit, a condenserevaporator element comprising atubular passageway forming means, a liquid container located in saidpassageway and requiring flow of gases around it, a condenser shellconnected to said tubular passageway means beyond the liquid container,and a suinp located below the point of connection of the condensershell, said condenser shell having a closed tubeextending from it intosaid-passageway means having holes therein *for passage of refrigerantgases.

25. In a refrigeration unit, the combination of a generator-absorberhaving separate inflow and outflow passages, the latter protected by aliquid seal composed mainly of the liquid absorbent used, acondenser-evapo- U will not be destroyed in draining the conto providedenser-evaporator back into the generatorabsorber.

26. In a refrigeration unit, the combination of a generator-absorberhaving separate inflow and outflow passages, the latter protected by aliquid seal composed mainly of the liquid absorbent used, acondenser-evaporator, means for partially cooling the gases flowing fromthe generator before they reach the condenser-evaporator, baffling meansfor entrapping the mist of absorbent medium condensed by said partialcooling, and a sump to catch the entrapped particles, so that therefrigerating medium is substantially free of contained absorbent, whenit reaches the condenser-evaporator.

27. In a refrigerating unit, the combination of a generator-absorber, acondenserevaporator and passageways between them to provide separatepaths for flow of gases in opposing directions, with the passageway forthe generated gases having a seal, and the passageway for the gases tobe absorbed encling in an open topped tubular member spaced from andlocated closely below the level of the absorbent liquid at the start ofthe absorption so as to set up surface agitation thereof and enteringthe absorber from above to avoid a static head of liquid in thepassageway.

28. In a refrigerator unit, the combination of a generator-absorber, acondenserevaporator, and passageways between them separate paths forflow of gases out of and into the generator-absorber, the passagewayinto the generator-absorber having an unrestricted annular opening nearthe surface of the absorbent liquid at the start of absorption so as toset up surface agitation thereof and entering the absorber from above soas to avoid a static head of liquid in the passageway.

29. In a refrigeration unit, a generator-absorber having a sealed outlettherefrom, and

an inlet thereinto, the latter being arranged to carry the gases to beabsorbed, said inlet formed as a pipe which terminates in a spacedtubular member, open at the top, and forming an unrestricted openingnear the surface of the absorbent at the period when absorption beginsand enters the absorber from above so as to avoid a static head ofliquid in the passageway.

30. In a refrigeration apparatus, a genorator-absorber formed in theshape of a sphere, thereby providing the strongest shape for therequired solid content thereof, said sphere provided externally withheat radiating fins, thereby compensating for the restricted surface ofthe spherical body proportionate to its solid contents.

31. In an absorption system refrigerating device, a generator-absorbershell having an outlet passage for products of evaporation and a casinglocated on and in direct con tact with the generator-absorber shelladjacent the outlet passage adapted to retain a body of cooling liquidin place whereby an initial dehydration occurs at said outlet passage.

32. In combination with a vessel for containing cooling liquid, aportable refrigeration unit comprising a generator-absorber receptacle,and a condenser-evaporator receptacle, means extending between saidreceptacle joining them together as a unit, and means on said unitcooperating with the vessel for holding the condenser-evaporatorsubmerged in the liquid therein when the condenser-evaporator, becauseof its empty condition would otherwise float on the surface of saidliquid.

33. In combination with a vessel for containing cooling liquid, aportable refrigeration unit comprising a generator-absorber receptacle,and a condenser-evaporator receptacle, means extending between saidreceptacles joining them together as a unit, and means in connectionwith the vessel for holding the condenser-evaporator submerged in theliquid therein when the condenser-evaporator, because of its emptycondition would otherwise float on the Surface of said liquid, saidmeans comprising an element exterior of the vessel for holding the unitin a vertical position, whereby the weight of the generator-absorberholds down the condenserevaporator.

3%, In combination with a vessel for containing cooling liquid, aportable refrigeration unit comprising a generator-absorber receptacle,and a condenser-evaporator receptacle, means extending between saidreceptacles joining them together as a unit, and means in connectionwith the vessel for holding the condenser-evaporator submerged in theliquid therein when the condenser-evaporator, because of its emptycondition would otherwise float on the surface of said liquid, saidmeans comprising a bracket against which the generator-absorberreceptacle bears, thus preventing tipping of the device.

35. In combination with a vessel for containing cooling liquid, aportable refrigeration unit comprising a generator-absorber receptacle,tacle, means extending between said receptacles joining them together asa unit, and means in connection with the vessel for holding thecondenser-evaporator submerged in the liquid therein when thecondenser-evaporator, because of its empty condition would otherwisefloat on the surface of said liquid, said means comprising a bracketagainst which the generator-absorber receptacle bears, thus preventingtipping of the device, and a member located on the joining means betweenthe receptacles which engages the edge of the said vessel.

DAVID FORBES KEITH.

and a condenser-evaporator recep-

